class1.cs

C#开发教程 由浅入深 配有实例 是初学者的好帮手

using System;

namespace DefaultCtors
{
	class File
	{
	}

	class CommaDelimitedFile
	{
		// these two lines are the same
//		public CommaDelimitedFile(String fileName) : this()
		public CommaDelimitedFile(String fileName)
		{
			Console.WriteLine("Constructed with a file name");
		}

		public CommaDelimitedFile(File file)
		{
			Console.WriteLine("Constructed with a file object");
		}
		public CommaDelimitedFile() : this("Default string")
		{
		}
	}

	class Class1
	{
		[STAThread]
		static void Main(string[] args)
		{
			File file = new File();
			CommaDelimitedFile file2 = 
				new CommaDelimitedFile(file);
			CommaDelimitedFile file3 = 
				new CommaDelimitedFile("Some file name");

			CommaDelimitedFile file4 = 
				new CommaDelimitedFile();
		}
	}
}